2-Ethylhexanol, a branched chain alcohol, is used in the manufacture of a variety of products due to its versatility as a chemical intermediate. For example, 2-ethylhexanol can be converted into a variety of useful esters or used as a chain terminator in the manufacture of condensation polymers.
Methods for producing 2-ethylhexanol from 1-butanol are known. For example, U.S. Pat. No. 3,558,716 discloses that according to the Guerbet reaction, beta-branched primary alcohols are obtained by reacting primary alcohols which in beta position to the hydroxyl group have a methylene (CH2) group, in the presence of alkali and at elevated temperature. Equation (1) in the patent shows 2-ethylhexanol being formed from 1-butanol.
Carlini et al. disclose the selective synthesis of 2-ethyl-1-hexanol from n-butanol through the Guerbet reaction by using bifunctional catalysts based on copper or palladium precursors and sodium butoxide (Journal of Molecular Catalysis A: Chemical 212 (2004) 65-70).
Published US Patent Application 2007/0255079 A1 discloses a process for producing, from ethanol as a raw material, higher molecular weight alcohols having an even number of carbon atoms, such as 1-butanol, hexanol, octanol and decanol. The higher molecular weight alcohols are produced from ethanol using calcium phosphate-based compounds such as hydroxyapatite Ca10(PO4)6(OH)2, tricalcium phosphate Ca3(PO4)2, calcium monohydrogen phosphate CaHPO4.(0-2)H2O, calcium diphosphate Ca2P2O7, octacalcium phosphate Ca8H2(PO4)6.5H2O, tetracalcium phosphate Ca4(PO4)2O, or amorphous calcium phosphate Ca3(PO4)2.nH2O as a catalyst, the contact time being 0.4 second or longer.
Processes to produce 2-ethylhexanol from a reactant stream comprising 1-butanol continue to be sought. Particularly desired are vapor phase processes employing catalyst compositions which can provide good conversions of 1-butanol to 2-ethylhexanol with good selectivity while exhibiting long catalytic lifetimes and without the need to add base during the reaction to form 2-ethylhexanol. Such processes to produce 2-ethylhexanol are desired for the economic benefits they can offer.